Turbine assembly with spring biased clearance sensor mount

Abstract

A turbine assembly includes a bladed rotor mounted for rotation about an axis of the gas turbine engine, a case assembly, and an actively-cooled tip clearance system. The tip clearance system includes a tip clearance sensor located radially outward of an inner case of the case assembly. The actively-cooled tip clearance system includes a sensor is configured to monitor a tip clearance formed between the bladed rotor and the case assembly during operation of the gas turbine engine.

What is claimed is: 
     
       1. A turbine assembly adapted for use in a gas turbine engine, the turbine assembly comprising
 a bladed rotor mounted for rotation about an axis of the gas turbine engine, 
 a case assembly including an inner case that extends circumferentially around the bladed rotor to define an outer boundary of a gas path of the turbine assembly to block combustion products from moving through the gas path of the turbine assembly without interaction with blades included in the bladed rotor and an outer case that extends circumferentially around the inner case and is spaced radially outward of the inner case to define an annular plenum therebetween, and 
 a tip clearance system including a tip clearance sensor located in the annular plenum to engage the inner case radially outward of the gas path of the turbine assembly and configured to monitor a tip clearance formed between the bladed rotor and the inner case during operation of the gas turbine engine and a sensor mount that extends between the outer case and the tip clearance sensor to apply a bias force to the tip clearance sensor to urge the tip clearance sensor radially inward into engagement with the inner case and maintain the engagement between the tip clearance sensor and the inner case, 
 wherein the inner case is located radially between a terminal end of the tip clearance sensor and the blades of the bladed rotor. 
 
     
     
       2. The turbine assembly of  claim 1 , wherein the tip clearance sensor extends radially outward through the outer case and wherein the sensor mount includes a mount bracket coupled to the outer case radially outward of the outer case and at least one bias element arranged radially between the mount bracket and the tip clearance sensor to apply the bias force to the tip clearance sensor to urge the tip clearance sensor radially inward into engagement with the inner case. 
     
     
       3. The turbine assembly of  claim 2 , wherein the sensor mount further includes a collar coupled to the tip clearance sensor to define a shoulder surface and the at least one bias element is arranged radially between the mount bracket and the collar. 
     
     
       4. The turbine assembly of  claim 3 , wherein the sensor mount further includes a cover plate coupled to the outer case radially inward of the collar to locate the at least one bias element and the collar radially between the mount bracket and the cover plate and a seal member arranged to extend between the cover plate and the tip clearance sensor to seal therebetween. 
     
     
       5. The turbine assembly of  claim 2 , wherein the at least one bias element is arranged directly between the mount bracket and the tip clearance sensor to apply the bias force to the tip clearance sensor. 
     
     
       6. The turbine assembly of  claim 5 , wherein the sensor mount further includes a cover plate coupled to the mount bracket radially outward of the mount bracket and a seal member arranged to extend between the cover plate, the mount bracket, and the tip clearance sensor to seal therebetween. 
     
     
       7. The turbine assembly of  claim 1 , wherein the tip clearance sensor includes a main housing body that engages the inner case and at least one shaft that extends radially outward away from the main housing body to the sensor mount. 
     
     
       8. The turbine assembly of  claim 7 , wherein the sensor mount includes a mount bracket coupled to the outer case radially outward of the outer case and a bias element arranged around the at least one shaft of the tip clearance sensor and radially between the mount bracket and the tip clearance sensor to apply the bias force to the tip clearance sensor to urge the tip clearance sensor radially inward into engagement with the inner case. 
     
     
       9. The turbine assembly of  claim 7 , wherein the tip clearance sensor includes at least two shafts that each extend radially outward from the main housing body, and wherein the sensor mount includes a mount bracket coupled to the outer case radially outward of the outer case and a bias element arranged in a gap formed between the at least two shafts to locate the bias element radially between the mount bracket and the tip clearance sensor to apply the bias force to the tip clearance sensor to urge the tip clearance sensor radially inward into engagement with the inner case. 
     
     
       10. The turbine assembly of  claim 1 , wherein the sensor mount includes at least one bias element configured to apply the bias force to the tip clearance sensor to urge the tip clearance sensor radially inward into engagement with the inner case and wherein the at least one bias element is one of a conical spring washers, a conical spring, a coil spring, a wave spring, a leaf spring, and a bellows seal. 
     
     
       11. A gas turbine engine comprising
 a compressor configured to compress air drawn in to the gas turbine engine and discharge pressurized air, 
 a combustor configured to mix fuel with the pressurized air from the compressor and ignites the fuel to produce hot, high pressure combustion products, 
 a turbine assembly configured to receive the combustion products and to extract mechanical work form the combustion products as the combustion products move through the turbine assembly, the turbine assembly including
 a bladed rotor mounted for rotation about an axis of the gas turbine engine, 
 a case assembly including an inner case that extends circumferentially around the bladed rotor and an outer case that extends circumferentially around the inner case and is spaced radially outward of the inner case to define an annular plenum therebetween, and 
 a tip clearance system including a tip clearance sensor located in the annular plenum to engage the inner case and configured to monitor a tip clearance formed between the bladed rotor and the inner case during operation of the gas turbine engine and a sensor mount that extends between the outer case and the tip clearance sensor to apply a bias force to the tip clearance sensor to urge the tip clearance sensor radially inward into engagement with the inner case and maintain the engagement between the tip clearance sensor and the inner case, 
 
 wherein the tip clearance sensor does not extend through the inner case. 
 
     
     
       12. The turbine assembly of  claim 11 , wherein the tip clearance sensor extends radially outward through the outer case and wherein the sensor mount includes a mount bracket coupled to the outer case radially outward of the outer case and at least one bias element arranged radially between the mount bracket and the tip clearance sensor to apply the bias force to the tip clearance sensor to urge the tip clearance sensor radially inward into engagement with the inner case. 
     
     
       13. The turbine assembly of  claim 12 , wherein the sensor mount further includes a collar coupled to the tip clearance sensor to define a shoulder surface and the at least one bias element is arranged radially between the mount bracket and the collar, a cover plate coupled to the outer case radially inward of the collar to locate the at least one bias element and the collar radially between the mount bracket and the cover plate, and a seal member arranged to extend between the cover plate and the tip clearance sensor to seal therebetween. 
     
     
       14. The turbine assembly of  claim 12 , wherein the at least one bias element is arranged directly between the mount bracket and the tip clearance sensor to apply the bias force to the tip clearance sensor. 
     
     
       15. The turbine assembly of  claim 14 , wherein the sensor mount further includes a cover plate coupled to the mount bracket radially outward of the mount bracket and a seal member arranged to extend between the cover plate, the mount bracket, and the tip clearance sensor to seal therebetween. 
     
     
       16. The turbine assembly of  claim 11 , wherein the tip clearance sensor includes a main housing body that engages the inner case and at least one shaft that extends radially outward away from the main housing body to the sensor mount. 
     
     
       17. The turbine assembly of  claim 16 , wherein the sensor mount includes a mount bracket coupled to the outer case radially outward of the outer case and a bias element arranged around the at least one shaft of the tip clearance sensor and radially between the mount bracket and the tip clearance sensor to apply the bias force to the tip clearance sensor to urge the tip clearance sensor radially inward into engagement with the inner case. 
     
     
       18. The turbine assembly of  claim 16 , wherein the tip clearance sensor includes at least two shafts that each extend radially outward from the main housing body, and wherein the sensor mount includes a mount bracket coupled to the outer case radially outward of the outer case and a bias element arranged in a gap formed between the at least two shafts to locate the bias element radially between the mount bracket and the tip clearance sensor to apply the bias force to the tip clearance sensor to urge the tip clearance sensor radially inward into engagement with the inner case. 
     
     
       19. The turbine assembly of  claim 11 , wherein the sensor mount includes at least one bias element configured to apply the bias force to the tip clearance sensor to urge the tip clearance sensor radially inward into engagement with the inner case and wherein the at least one bias element is one of a conical spring washer, a conical spring, a coil spring, a wave spring, a leaf spring, and a bellows seal. 
     
     
       20. A method comprising
 providing a turbine assembly adapted for use in a gas turbine engine, the turbine assembly comprising
 a bladed rotor mounted for rotation about an axis of the gas turbine engine, 
 a case assembly including an inner case that extends circumferentially around the bladed rotor and an outer case that extends circumferentially around the inner case and is spaced radially outward of the inner case to define an annular plenum therebetween, and 
 a tip clearance system including a tip clearance sensor located in the annular plenum to engage the inner case and configured to monitor a tip clearance formed between the bladed rotor and the inner case during operation of the gas turbine engine and a sensor mount that extends between the outer case and the tip clearance sensor to couple the tip clearance sensor to the case assembly, and 
 
 applying a bias force to the tip clearance sensor to urge the tip clearance sensor radially inward into engagement with the inner case and maintain the engagement between the tip clearance sensor and the inner case, 
 wherein the inner case is located radially between a terminal end of the tip clearance sensor and the blades of the bladed rotor.